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arXiv · 1701.02811

Statistical Challenges in Fitting Stellar Orbits around the Supermassive Black Hole at the Galactic Center

Gregory Martinez·Kelly Kosmo·Aurelien Hees·Joseph Ahn·Andrea Ghez
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Abstract

Over two decades of astrometric and radial velocity data of short period stars in the Galactic center have the potential to provide unprecedented tests of General Relativity and insight into the astrophysics of supermassive black holes. Fundamental to this is understanding the underlying statistical issues of fitting stellar orbits. Unintended prior effects can obscure actual physical effects from General Relativity and the underlying extended mass distribution. At the heart of this is dealing with large parameter spaces inherent to multi star fitting and ensuring acceptable coverage properties of the resulting confidence intervals within the Bayesian framework. This proceeding will detail some of the UCLA Galactic Center Group's analysis and work in addressing these statistical issues.

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Gregory Martinez, Kelly Kosmo, Aurelien Hees, Joseph Ahn, Andrea Ghez. 2017-01-10. Statistical Challenges in Fitting Stellar Orbits around the Supermassive Black Hole at the Galactic Center. https://doi.org/10.1017/s1743921316012175

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